Carry out a series of studies designed to obtain detailed information on the pharmacology of adriamycin derivatives to be selected and supplied by the contractor. These drugs will be studied both as single agents and in combination with other agents. These studies will be carried out in tumor-bearing mice at various stages of tumor growth. It will require the ability to develop sensitive techniques for drug and metabolite detection and quantitation. Effort will be made to correlate the concentrations of these agents and their active metabolites in blood, tumor, and normal tissues (particularly the small intestine and bone marrow) with their toxic activity. Measurements of toxic activity should include: deptresion of bone marrow poliferative capacity; damage to intestional epithelium; degree of tumor cell kill; and immunosuppression. Comparison of the effects of significant metabolites found in vivo will also be made with the parent drug in vitro employing a cell kill assay technique.